CA2137996C - Treatment process for contaminated waste - Google Patents
Treatment process for contaminated waste Download PDFInfo
- Publication number
- CA2137996C CA2137996C CA002137996A CA2137996A CA2137996C CA 2137996 C CA2137996 C CA 2137996C CA 002137996 A CA002137996 A CA 002137996A CA 2137996 A CA2137996 A CA 2137996A CA 2137996 C CA2137996 C CA 2137996C
- Authority
- CA
- Canada
- Prior art keywords
- calcium
- sulfide
- contaminated waste
- amount
- calcium carbonate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
- A62D3/00—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances
- A62D3/30—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances by reacting with chemical agents
- A62D3/33—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances by reacting with chemical agents by chemical fixing the harmful substance, e.g. by chelation or complexation
-
- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
- A62D2101/00—Harmful chemical substances made harmless, or less harmful, by effecting chemical change
- A62D2101/20—Organic substances
- A62D2101/24—Organic substances containing heavy metals
-
- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
- A62D2101/00—Harmful chemical substances made harmless, or less harmful, by effecting chemical change
- A62D2101/40—Inorganic substances
- A62D2101/43—Inorganic substances containing heavy metals, in the bonded or free state
Landscapes
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Toxicology (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Processing Of Solid Wastes (AREA)
- Removal Of Specific Substances (AREA)
Abstract
A process for treating contaminated waste to stabilize environmentally harmful heavy metal. The contaminated waste is contacted with a mixture of (i) inorganic sulfide, (ii) calcium phosphate to prevent oxidation of the sulfide and (iii) calcium carbonate, the last acting as a base. Water is added to enhance mass transfer during the mixing. The calcium carbonate may be mixed with calcium oxide, to provide an additional base.
Description
TREATMENT PROCESS FOR CONTAMINATED WASTE
This invention relates to a process to treat contaminated waste, particularly waste containing toxic metals, to render the toxic metals harmless to the environment.
The treating of heavy metals in waste such as soil, ash, sludge, baghouse dust and sediments, to stabilize the metals, is of increasing importance. These metals can become mobile, enter the ground water and cause environmental damage to ecosystems. For example, it is of significance where land is rezoned from industrial to recreational or housing use. A particular concern is where the soil, either from natural causes or because of industry previously carried out on the site, contains elements toxic to the environment. These elements can be leached out, become mobile, and enter the water table where they are spread rapidly throughout the environment, causing considerable environmental damage.
It is known to stabilize these elements into a water insoluble form so that they cannot be leached from the contaminated waste into the environment. Existing methods have achieved limited success and the present invention seeks to improve on these existing methods.
Accordingly, the present invention provides a process for treating contaminated waste to stabilize environmentally harmful heavy metal comprising (a) contacting the contaminated waste with a mixture of (i) a sulfide selected from the group consisting of calcium sulfide, calcium polysulfide, sodium sulfide, sodium hydrosulfide and iron sulfide, (ii) calcium phosphate to prevent oxidation of the sulfide and (iii) calcium carbonate and (b) adding water to enhance mass transfer during mixing.
This invention relates to a process to treat contaminated waste, particularly waste containing toxic metals, to render the toxic metals harmless to the environment.
The treating of heavy metals in waste such as soil, ash, sludge, baghouse dust and sediments, to stabilize the metals, is of increasing importance. These metals can become mobile, enter the ground water and cause environmental damage to ecosystems. For example, it is of significance where land is rezoned from industrial to recreational or housing use. A particular concern is where the soil, either from natural causes or because of industry previously carried out on the site, contains elements toxic to the environment. These elements can be leached out, become mobile, and enter the water table where they are spread rapidly throughout the environment, causing considerable environmental damage.
It is known to stabilize these elements into a water insoluble form so that they cannot be leached from the contaminated waste into the environment. Existing methods have achieved limited success and the present invention seeks to improve on these existing methods.
Accordingly, the present invention provides a process for treating contaminated waste to stabilize environmentally harmful heavy metal comprising (a) contacting the contaminated waste with a mixture of (i) a sulfide selected from the group consisting of calcium sulfide, calcium polysulfide, sodium sulfide, sodium hydrosulfide and iron sulfide, (ii) calcium phosphate to prevent oxidation of the sulfide and (iii) calcium carbonate and (b) adding water to enhance mass transfer during mixing.
The calcium phosphate is added to prevent re-mobilization of the contaminating metals by precipitating any available ferric iron so that the redox potential is insufficient to oxidize metallic sulfide. The calcium phosphate is preferably used in the amount of 1 to 3% by weight of the contaminated waste. The preferred calcium phosphate is calcium hydrogen phosphate.
The calcium carbonate acts as a basic compound and may be supplemented by calcium oxide. The base component is used in an amount sufficient to provide two or more times the amount of neutralization capability as there is acid generation potential from the added sulfide. That is the addition of calcium carbonate (and, if present, the calcium oxide) provides an additional safety measure by supplying in excess of 2 parts neutralization potential for each part of maximum potential acidity.
The calcium carbonate is preferably fine, that is of small particle size. The base component is used to ensure that the final pH of the treated waste is greater than about 8.5.
The sulfide is preferably used in an amount of 1 to 12% by weight of the contaminated waste, the actual amount depending on the concentration of contaminant present. The sulfide, calcium phosphate, calcium carbonate and, if present, the calcium oxide, are mixed prior to use.
The addition of the base (calcium carbonate and, perhaps, calcium oxide) and the calcium phosphate increases the pH of the treated waste to allow converting a portion of the metals to phosphates and carbonates. The pH increase to greater than 8.5 also prevents the generation of hydrogen sulfide gas.
The calcium carbonate acts as a basic compound and may be supplemented by calcium oxide. The base component is used in an amount sufficient to provide two or more times the amount of neutralization capability as there is acid generation potential from the added sulfide. That is the addition of calcium carbonate (and, if present, the calcium oxide) provides an additional safety measure by supplying in excess of 2 parts neutralization potential for each part of maximum potential acidity.
The calcium carbonate is preferably fine, that is of small particle size. The base component is used to ensure that the final pH of the treated waste is greater than about 8.5.
The sulfide is preferably used in an amount of 1 to 12% by weight of the contaminated waste, the actual amount depending on the concentration of contaminant present. The sulfide, calcium phosphate, calcium carbonate and, if present, the calcium oxide, are mixed prior to use.
The addition of the base (calcium carbonate and, perhaps, calcium oxide) and the calcium phosphate increases the pH of the treated waste to allow converting a portion of the metals to phosphates and carbonates. The pH increase to greater than 8.5 also prevents the generation of hydrogen sulfide gas.
The invention is illustrated in the following example:
Example:
Soil samples were prepared and treated by the process according to the present invention and compared to untreated samples. The treated and untreated samples were subjected to the Toxicity Characteristic Leaching Procedure (TCLP) as described in "Hazardous Waste Management System; Identification and Listing of Hazardous Waste; Toxicity Characteristics Revisions;
Final Rule. Environmental Protection Agency, Federal Register. Part II. 40 CFR Part 261 et al. March 29, 1990. The following results were achieved:
Table 1 Waste Contaminant Untreated Treated criteria for Source Metal TCLP (mg/L) TCLP (mg/L) Safe Disposal (mg/L) Auto Lead 55 <0.10 5 Recycler soil Pickling Lead 650 0.74 5 sludge Foundry Lead 400 <0.05 5 Soil Although it is known from the prior art that sulfide alone can be used to stabilize toxic metals in contaminated waste, the problem with the use of sulfide alone is concern for subsequent oxidation of the sulfide and generation of acid which re-mobilizes contaminant metals - see Conner, Jesse R., "Chemical Fixation and Solidification of Hazardous Wastes", Van Nostrand Reinhold, New York, New York. Library of Congress TD1060.C66 1990. p 83. The process of the invention mitigates this concern for the reactivity of the metallic sulfides which occurs by the reaction with ferric iron.
The process of the present invention incorporates phosphate which precipitates any available ferric iron so that the redox potential is insufficient to oxidize metallic sulfide - see Renton J.J. et al., "The use of Phosphate Materials as Ameliorants for Acid Mine Drainage", Inf. Cir - US Bur. of Mines, 1988 Number IC
9183, Mine Drain. Surf. Mine Reclam., Vol. 1 pp 67-75 and Stiller A.H. et al., "An Experimental Evaluation of the Use of Rock Phosphate (Apatite) for the Amelioration of Acid-Producing Coal Mine Waste", Mining Science &
Technology v9 n3 Nov. 1989 pp. 283-287.
Although the forgoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will be readily apparent to those of ordinary skill in the art in light of the teachings of this invention that certain changes and modifications may be made thereto without departing from the spirit or scope of the appended claims.
Example:
Soil samples were prepared and treated by the process according to the present invention and compared to untreated samples. The treated and untreated samples were subjected to the Toxicity Characteristic Leaching Procedure (TCLP) as described in "Hazardous Waste Management System; Identification and Listing of Hazardous Waste; Toxicity Characteristics Revisions;
Final Rule. Environmental Protection Agency, Federal Register. Part II. 40 CFR Part 261 et al. March 29, 1990. The following results were achieved:
Table 1 Waste Contaminant Untreated Treated criteria for Source Metal TCLP (mg/L) TCLP (mg/L) Safe Disposal (mg/L) Auto Lead 55 <0.10 5 Recycler soil Pickling Lead 650 0.74 5 sludge Foundry Lead 400 <0.05 5 Soil Although it is known from the prior art that sulfide alone can be used to stabilize toxic metals in contaminated waste, the problem with the use of sulfide alone is concern for subsequent oxidation of the sulfide and generation of acid which re-mobilizes contaminant metals - see Conner, Jesse R., "Chemical Fixation and Solidification of Hazardous Wastes", Van Nostrand Reinhold, New York, New York. Library of Congress TD1060.C66 1990. p 83. The process of the invention mitigates this concern for the reactivity of the metallic sulfides which occurs by the reaction with ferric iron.
The process of the present invention incorporates phosphate which precipitates any available ferric iron so that the redox potential is insufficient to oxidize metallic sulfide - see Renton J.J. et al., "The use of Phosphate Materials as Ameliorants for Acid Mine Drainage", Inf. Cir - US Bur. of Mines, 1988 Number IC
9183, Mine Drain. Surf. Mine Reclam., Vol. 1 pp 67-75 and Stiller A.H. et al., "An Experimental Evaluation of the Use of Rock Phosphate (Apatite) for the Amelioration of Acid-Producing Coal Mine Waste", Mining Science &
Technology v9 n3 Nov. 1989 pp. 283-287.
Although the forgoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will be readily apparent to those of ordinary skill in the art in light of the teachings of this invention that certain changes and modifications may be made thereto without departing from the spirit or scope of the appended claims.
Claims (7)
1. A process for treating contaminated waste to stabilize environmentally harmful heavy metal comprising:
(a) contacting the contaminated waste with a mixture of (i) a sulfide selected from the group consisting of calcium sulfide, calcium polysulfide, sodium sulfide, sodium hydrosulfide and iron sulfide, (ii) calcium phosphate to prevent oxidation of the sulfide and (iii) calcium carbonate acting as a base; and (b) adding water to enhance mass transfer during mixing.
(a) contacting the contaminated waste with a mixture of (i) a sulfide selected from the group consisting of calcium sulfide, calcium polysulfide, sodium sulfide, sodium hydrosulfide and iron sulfide, (ii) calcium phosphate to prevent oxidation of the sulfide and (iii) calcium carbonate acting as a base; and (b) adding water to enhance mass transfer during mixing.
2. The process claimed in claim 1 in which the calcium phosphate is used in the amount of 1 to 3% by weight of contaminated waste.
3. The process as claimed in claim 1 in which the calcium phosphate is calcium hydrogen phosphate.
4. The process as claimed in claim 1 in which calcium oxide is added to the mixture, the calcium carbonate and calcium oxide both acting as a base.
5. The process as claimed in claim 1 in which the calcium carbonate is used in an amount sufficient to provide two or more times the amount of neutralization capability as there is acid generation potential from the sulfide added.
6. The process as claimed in claim 4 in which the calcium carbonate and the calcium oxide are used in an amount sufficient to provide two or more times the amount of neutralization capability.
7. The process as claimed in claim 1 in which the sulfide is used in an amount of 1 to 12% by weight of the contaminated waste.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US33978494A | 1994-11-15 | 1994-11-15 | |
US08/339,784 | 1994-11-15 |
Publications (2)
Publication Number | Publication Date |
---|---|
CA2137996A1 CA2137996A1 (en) | 1996-05-16 |
CA2137996C true CA2137996C (en) | 2007-10-16 |
Family
ID=23330574
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA002137996A Expired - Fee Related CA2137996C (en) | 1994-11-15 | 1994-12-13 | Treatment process for contaminated waste |
Country Status (10)
Country | Link |
---|---|
US (1) | US5898093A (en) |
EP (1) | EP0790846B1 (en) |
CN (1) | CN1116082C (en) |
AT (1) | ATE187089T1 (en) |
AU (1) | AU3468095A (en) |
CA (1) | CA2137996C (en) |
DE (1) | DE69513684D1 (en) |
PL (1) | PL180645B1 (en) |
PT (1) | PT790846E (en) |
WO (1) | WO1996014901A1 (en) |
Families Citing this family (29)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5877393A (en) * | 1996-08-30 | 1999-03-02 | Solucorp Industries, Ltd. | Treatment process for contaminated waste |
BE1010618A3 (en) * | 1996-09-12 | 1998-11-03 | Revatech S A | Waste water treatment process of solidification of smoke incinerateurs of garbage and industrial liquid and solid waste. |
US6337058B1 (en) | 1996-09-16 | 2002-01-08 | E&C Williams Inc. | Process for producing calcium sulfide |
DE19717122A1 (en) * | 1997-04-23 | 1998-10-29 | Kali Umwelttechnik Sondershaus | Mineral building material |
FR2768933B1 (en) * | 1997-09-30 | 1999-11-12 | Rhodia Chimie Sa | HEAVY METAL REMOVAL AGENT COMPRISING A PHOSPHATE COMPOUND |
AU1656999A (en) * | 1997-12-19 | 1999-07-12 | Solucorp Industries Ltd. | Integrated fixation systems |
US6838504B1 (en) | 1998-05-06 | 2005-01-04 | Solucorp Industries Ltd. | Integrated fixation systems |
AU3695499A (en) * | 1998-05-06 | 1999-11-23 | Solucorp Industries Ltd. | Integrated fixation systems |
US6797178B2 (en) * | 2000-03-24 | 2004-09-28 | Ada Technologies, Inc. | Method for removing mercury and mercuric compounds from dental effluents |
US6911570B2 (en) * | 2000-11-28 | 2005-06-28 | Ada Technologies, Inc. | Method for fixating sludges and soils contaminated with mercury and other heavy metals |
US6682713B2 (en) | 2001-01-26 | 2004-01-27 | Tosoh Corporation | Iron sulfides, processes for producing the same, iron sulfide mixture, heavy metal treating agent, and method of treating with the agent |
US6797171B2 (en) * | 2001-05-14 | 2004-09-28 | Robert W. Bartlett | In situ anaerobic bioremediation of earth and sold waste contaminants using organic/water emulsions |
GB2381884A (en) * | 2001-07-16 | 2003-05-14 | Pablo D Cappellini | A search engine of flexibly-defined paths applicable to the search of transportation-related routes |
US7183235B2 (en) * | 2002-06-21 | 2007-02-27 | Ada Technologies, Inc. | High capacity regenerable sorbent for removing arsenic and other toxic ions from drinking water |
WO2005032394A2 (en) * | 2003-10-01 | 2005-04-14 | Ada Technologies, Inc. | System for removing mercury and mercuric compounds from dental wastes |
US20060280907A1 (en) * | 2005-06-08 | 2006-12-14 | Whitaker Robert H | Novel mineral composition |
US7833339B2 (en) * | 2006-04-18 | 2010-11-16 | Franklin Industrial Minerals | Mineral filler composition |
US7651559B2 (en) * | 2005-11-04 | 2010-01-26 | Franklin Industrial Minerals | Mineral composition |
EP2040837B1 (en) * | 2006-07-04 | 2012-06-20 | Gaston Glock | Method for the removal of heavy metals |
WO2010141449A1 (en) * | 2009-06-03 | 2010-12-09 | First Solar, Inc. | Self-remediating photovoltaic module |
MX2013011335A (en) * | 2011-03-29 | 2014-03-27 | Heritage Environmental Serv | Stabilizing hazardous wastes using waste byproducts. |
CN102701554A (en) * | 2012-06-28 | 2012-10-03 | 郑州大学 | Stabilizing agent for heavy-metal polluted sediment treatment |
CN102921142B (en) * | 2012-11-06 | 2016-04-27 | 莱沃睿智绿色科技(北京)有限公司 | Heavy metal contaminants immobilized reagent composition and immobilization administering method |
WO2014143945A2 (en) | 2013-03-15 | 2014-09-18 | ADA-ES, Inc. | Methods for solidification and stabilization of industrial byproducts |
US10809677B2 (en) | 2014-06-12 | 2020-10-20 | ADA-ES, Inc. | Methods to substantially optimize concentration of materials in an output stream |
CN106565199A (en) * | 2016-10-10 | 2017-04-19 | 无锡易水元资源循环科技有限公司 | Method for producing brick by using water treatment sludge |
US10926308B2 (en) | 2017-09-22 | 2021-02-23 | HMR Solutions, Inc. | Method and reagent system for treating mercury-contaminated material |
CN108913153A (en) * | 2018-08-08 | 2018-11-30 | 环境保护部华南环境科学研究所 | A kind of composite material suitable for heavy-metal composite pollution farmland safe utilization |
CN110279975A (en) * | 2019-07-23 | 2019-09-27 | 哈德逊(苏州)水技术有限公司 | Incineration of refuse flyash curing agent |
Family Cites Families (21)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3817859A (en) * | 1972-03-29 | 1974-06-18 | Texaco Inc | Waste water treatment method |
US4354942A (en) * | 1980-11-26 | 1982-10-19 | Olin Corporation | Stabilization of mercury in mercury-containing materials |
US4364773A (en) * | 1980-12-23 | 1982-12-21 | Marcel Veronneau | Waste metal conversion process and products |
US4629509A (en) * | 1985-06-24 | 1986-12-16 | Allied Corporation | Immobilization of lead and cadmium in fly ash |
US4737356A (en) * | 1985-11-18 | 1988-04-12 | Wheelabrator Environmental Systems Inc. | Immobilization of lead and cadmium in solid residues from the combustion of refuse using lime and phosphate |
US4687373A (en) * | 1986-05-21 | 1987-08-18 | Lopat Industries, Inc. | Composition to encapsulate toxic metal and/or organic pollutants from wastes |
DE3632365A1 (en) * | 1986-09-24 | 1988-03-31 | Friedrich Boelsing | METHOD FOR IMMOBILIZING POLLUTANTS IN THE FLOOR OR FLOOR-LIKE MATERIALS |
DE3918292C2 (en) * | 1988-10-04 | 1993-11-25 | Steinmueller Gmbh L & C | Process for the treatment of fly ash containing heavy metals from the flue gas of incineration plants, in particular waste or waste incineration plants |
US5193936B1 (en) * | 1990-03-16 | 1996-03-19 | Maecorp Inc | Fixation and stabilization of lead in contaminated soil and solid waste |
US5527982A (en) * | 1990-03-16 | 1996-06-18 | Sevenson Environmental Services, Inc. | Fixation and stabilization of metals in contaminated materials |
US5037479A (en) * | 1990-04-20 | 1991-08-06 | Rmt, Inc. | Method for reduction of heavy metal leaching from hazardous waste under acidic and nonacidic conditions |
US5139365A (en) * | 1990-09-04 | 1992-08-18 | Warren Chesner | Process for waste injection into landfills for waste management, landfill reclamation, enhanced biodegradation and enhanced methane gas generation and recovery |
US5162600A (en) * | 1990-12-28 | 1992-11-10 | Rheox, Inc. | Method of treating lead contaminated soil |
US5202033A (en) * | 1991-09-30 | 1993-04-13 | Rmt, Inc. | In situ method for decreasing heavy metal leaching from soil or waste |
SE500177C2 (en) * | 1992-05-06 | 1994-05-02 | Tord Georg Eriksson | Process for simultaneous reduction of residues of heavy metals and oil in oil-laden wastewater |
FR2694710B1 (en) * | 1992-08-14 | 1994-11-04 | Secomi | Process for neutralizing heavy metals contained in waste incineration residues. |
US5536899A (en) * | 1993-03-12 | 1996-07-16 | Forrester; Keith E. | Stabilization of lead bearing waste |
US5397478A (en) * | 1993-08-13 | 1995-03-14 | Sevenson Environmental Services, Inc. | Fixation and stabilization of chromium in contaminated materials |
US5512702A (en) * | 1993-11-08 | 1996-04-30 | The Ohio State University Research Foundation | Method for in-situ immobilization of lead in contaminated soils, wastes, and sediments using solid calcium phosphate materials |
CN1037197C (en) * | 1994-01-09 | 1998-01-28 | 高尚俭 | Method and apparatus for extracting arsenic from waste water containing arsenic |
US5637355A (en) * | 1996-04-22 | 1997-06-10 | Rmt, Inc. | Method of nonhazardous removal of paint containing heavy metals and coating preparation for performing the same |
-
1994
- 1994-12-13 CA CA002137996A patent/CA2137996C/en not_active Expired - Fee Related
-
1995
- 1995-09-15 DE DE69513684T patent/DE69513684D1/en not_active Expired - Lifetime
- 1995-09-15 CN CN95196253A patent/CN1116082C/en not_active Expired - Lifetime
- 1995-09-15 PL PL95320118A patent/PL180645B1/en not_active IP Right Cessation
- 1995-09-15 EP EP95931108A patent/EP0790846B1/en not_active Expired - Lifetime
- 1995-09-15 AU AU34680/95A patent/AU3468095A/en not_active Abandoned
- 1995-09-15 AT AT95931108T patent/ATE187089T1/en active
- 1995-09-15 WO PCT/CA1995/000527 patent/WO1996014901A1/en active IP Right Grant
- 1995-09-15 PT PT95931108T patent/PT790846E/en unknown
-
1997
- 1997-03-25 US US08/823,627 patent/US5898093A/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
CN1165486A (en) | 1997-11-19 |
EP0790846B1 (en) | 1999-12-01 |
CA2137996A1 (en) | 1996-05-16 |
AU3468095A (en) | 1996-06-06 |
CN1116082C (en) | 2003-07-30 |
PT790846E (en) | 2001-04-30 |
US5898093A (en) | 1999-04-27 |
PL320118A1 (en) | 1997-09-15 |
ATE187089T1 (en) | 1999-12-15 |
DE69513684D1 (en) | 2000-01-05 |
PL180645B1 (en) | 2001-03-30 |
WO1996014901A1 (en) | 1996-05-23 |
EP0790846A1 (en) | 1997-08-27 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
EEER | Examination request | ||
FZDC | Discontinued application reinstated | ||
MKLA | Lapsed |